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Plasma arc: municipal waste into energy, toothbrushes, roads, and even coral reefs?


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Hi all,

 

the most mind-blowing environmental chapter I've read on dealing with our wastes in a long time!

 

By Tom Blees, and backed by the likes of Dr James Hansen and Dr Barry Brooks. They're big fans of the IFR, but today I'm more interested in the plasma arc waste gasifier.

 

Grab a drink for a good 20 - 25 minute read, and tell me what you think.

 

My main concern is that if EVERYTHING went in here, including sewerage, surely we'd lose some other recycling opportunities:

 

* biomass in agricultural regions should be biochared for soil improvement

* the NPK in sewerage should be extracted as far as possible

* Maybe paper and glass should be recycled.

 

So where I am in Sydney we have 3 bins.

The Green bin is for biomass only.

 

Yellow bin is for glass, paper, and recyclable plastics. If using a plasma arc, forget recycling plastics... just collect the Paper and Glass and recycle those. (Paper saves trees, or can we grow hemp fast enough for all our paper needs? Even better, can we grow hemp in sewerage fields to not only grow fibre for paper but recycle some of the other biomass for fertiliser).

"Red" bin is for all other household waste.

 

But with a plasma burner, nastier stuff like e-waste, metals, paints, absestos, plastics, EVERYTHING else except maybe radioactive waste can go through the plasma arc.

 

Check it out.

 

Waste

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Rather than end up like Japan where some cities have 16 different LABELLED PLASTIC BAGS you have to sort your different kinds of waste into for recycling, which takes about half an hour to an hour each week and involves stacks of extra plastic bags in circulation, why not just chuck plastics into the plasma arc? Syngas can be made back into plastic. We're talking about a technology that allows asbestos sheeting and soiled disposable nappies to become your next toothbrush! Now that's recycling.

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Very interesting. Let's look at some numbers.

 

Average U.S. houshold uses 1 MWh per month, or 33 kWh per day.

 

The Japan plant produces about 5 MWh of electricity per day out of 150 tons garbage. That is 30 tons of garbage per 1 MWh of electricity. Since 1 MWh of electricity per day can power 30 households (at 33 kWh per day); then, 30 tons of garbage can power 30 households. Or, 30,000 kg of garbage per 30 homes. Or 1,000 kg of garbage per home per day to power it.

 

Average U.S. home needs 1,000 kg of garbage to power it per day, but average U.S. home generates about 10 kg of garbage per day. That is 100:1 ratio.

 

Conclusion, we simply need to consume more and create more garbage.

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You are naughty. :)

 

But I don't see this so much as an electricity generating scheme as a liquid fuel and petrochemical feedstock technology.

 

With Gen4 nukes we can run the world for 500 years on today's nuclear waste, without mining a single new ounce of uranium. So there's no shortage of electricity: but with peak oil bearing down on us there IS a shortage of liquid fuels in the pipeline. (Especially if offshore drilling gets banned after the recent gulf debacle).

 

So household waste and lawn clippings into jet-fuel and sunglasses and building materials sounds like a pretty good idea to me.

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I agree. It looks to be a waste management technology that may pay for itself.

 

But i can't help being naughty. Let's look at some more numbers. The cost of building this is about $200 million for 1000 tons of garbage per day. http://www.areavoices.com/gfhcitybeat/?blog=16409 . Out of 1000 tons per day, 510 tons can be sold in a form of electricty at 17 MWh, or 17,000 kWh per day (30 tons per 1 MWh). At $0.10 per kWh, 17,000 kWh will yield $1,700 per day, or ~ $620,000 annually.

 

Then, it would take 333 years for the plant to pay off. (I did not factor in the slag products such as rock wool.)

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Seems like you're twice as expensive as other captial assessments, and forgetting that some places might not be kitted out just to produce electricity. It all depends on what the local or national market most desires.

 

And don't forget the cost to dump waste. Tony Soprano wouldn't bother being in the waste business if there wasn't money in it.

 

Also don't forget selling methanol, ethanol, and jet fuel.

 

From page 10 of my link above.

 

Looking ahead to its many applications, the profit potential of plasma conversion is tremendous. Private companies could build facilities in developing countries and it would naturally be in their financial best interest to develop the garbage collection infrastructure to support their business. This is a perfect niche for the oil companies. The capital investment is fairly substantial. A plasma plant capable of processing 2000 tons per day — about the amount that a million people produce in the USA (likely less elsewhere, and much less in most places) — would cost about $250 million. The payback time on that investment would vary depending on what the syngas and slag would be used for, but current estimates are about twenty years. This can change considerably, though, since there are so many different uses for the syngas and slag. Also, that payback time is premised on the cost of building the first large plasma converter in the world. The first one always costs the most, of course. The price will surely drop substantially with future construction.

 

Tom Blee's source on the $$$ is USA today.

 

http://www.usatoday.com/news/nation/2006-09-09-fla-county-trash_x.htm

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Well, obviously we'll learn more about the economics of it as we gain more experience of it.

 

I'm personally against burning the gas to use to generate electricity: it's too valuable as a liquid fuel and feedstock. The gas leaves the chamber at 2000 degrees and is so hot at this stage the 'waste heat' of the gas can run steam turbines, so I've got no problem with that side of the operation. But actually burning the gas seems like a crime when 4th Gen nukes could run the world's ELECTRICITY needs for 500 years just of the nuclear waste we've already mined. As a peaknik, I'm concerned about how we're going to fly planes and do petrochemicals, so burning the syngas seems like a waste.

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